There are interesting opportunities to isolate or generate yeast
variants that perform better than the currently used strains. Therefore there
is the need of different strategies of strain selection and improvement
available for both conventional and nonconventional yeasts. Exploiting the
existing natural diversity and using techniques such as mutagenesis, protoplast
fusion, breeding, genome shuffling and directed evolution to generate
artificial diversity, or the use of genetic modification strategies to alter
traits in a more targeted way, have led to the selection of superior industrial
yeasts. Furthermore, recent technological advances allowed the development of
high-throughput techniques, such as ‘global transcription machinery
engineering’ (gTME), to induce genetic variation, providing a new source of
yeast genetic diversity.